Mitochondria directly influence fertilisation outcome in the pig

The mitochondrion is explicitly involved in cytoplasmic regulation and is the cell's major generator of ATP. Our aim was to determine whether mitochondria alone could influence fertilisation outcome. In vitro, oocyte competence can be assessed through the presence of glucose-6-phosphate dehydrogenase (G6PD) as indicated by the dye, brilliant cresyl blue (BCB). Using porcine in vitro fertilisation (IVF), we have assessed oocyte maturation, cytoplasmic volume, fertilisation outcome, mitochondrial number as determined by mtDNA copy number, and whether mitochondria are uniformly distributed between blastomeres of each embryo. After staining with BCB, we observed a significant difference in cytoplasmic volume between BCB positive (BCB+) and BCB negative (BCB-) oocytes. There was also a significant difference in mtDNA copy number between fertilised and unfertilised oocytes and unequal mitochondrial segregation between blastomeres during early cleavage stages. Furthermore, we have supplemented BCB- oocytes with mitochondria from maternal relatives and observed a significant difference in fertilisation outcomes following both IVF and intracytoplasmic sperm injection (ICSI) between supplemented, sham-injected and non-treated BCB- oocytes. We have therefore demonstrated a relationship between oocyte maturity, cytoplasmic volume, and fertilisation outcome and mitochondrial content. These data suggest that mitochondrial number is important for fertilisation outcome and embryonic development. Furthermore, a mitochondrial pre-fertilisation threshold may ensure that, as mitochondria are diluted out during post-fertilisation cleavage, there are sufficient copies of mtDNA per blastomere to allow transmission of mtDNA to each cell of the post-implantation embryo after the initiation of mtDNA replication during the early postimplantation stages

BLOOD WALLS

Ao longo do tempo contruimos idéias e objetivos, para poder traçar uma estratégia de montagem do nosso jogo. No qual se consiste em dois jogadadores e os seus objetivos em comum são eliminar um ou outro. Para que este objetivo se conclua o jogador deverá acessar o menu inicial e iniciar a sua partida através do mesmo. O jogo terá um menu um tanto sutil, contendo três opções básicas como “Sair”, uma pequena janela com instruções de como jogá-lo “Instruções”, e é claro a opção “Jogar”, que levará os jogadores a tela de seleção de personagens e logo em seguida, a luta. Ao iniciar a luta, o jogador deverá se utilizar de diversos golpes para despachar seu oponente, como socos e chutes, também poderá se utilizar a opção de bloqueio. A luta acabará quando a barra de vida de um dos oponentes chegar a zero

LHC and lepton flavour violation phenomenology of a left-right extension of the MSSM

We study the phenomenology of a supersymmetric left-right model, assuming minimal supergravity boundary conditions. Both left-right and (B-L) symmetries are broken at an energy scale close to, but significantly below the GUT scale. Neutrino data is explained via a seesaw mechanism. We calculate the RGEs for superpotential and soft parameters complete at 2-loop order. At low energies lepton flavour violation (LFV) and small, but potentially measurable mass splittings in the charged scalar lepton sector appear, due to the RGE running. Different from the supersymmetric 'pure seesaw' models, both, LFV and slepton mass splittings, occur not only in the left- but also in the right slepton sector. Especially, ratios of LFV slepton decays, such as Br(${\tilde\tau}_R \to \mu \chi^0_1$)/Br(${\tilde\tau}_L \to \mu \chi^0_1$) are sensitive to the ratio of (B-L) and left-right symmetry breaking scales. Also the model predicts a polarization asymmetry of the outgoing positrons in the decay $\mu^+ \to e^+ \gamma$, A ~ [0,1], which differs from the pure seesaw 'prediction' A=1$. Observation of any of these signals allows to distinguish this model from any of the three standard, pure (mSugra) seesaw setups.Comment: 43 pages, 17 figure

CONHECIMENTOS DE UNIVERSITÁRIOS DA ÁREA DA SAÚDE SOBRE CONTRACEPÇÃO E PREVENÇÃO DE DOENÇAS SEXUALMENTE TRANSMISSÍVEIS

Human sexuality is an important component in the individual’s formation. Sexuality has experienced important changes during human history, such as people’s access to information. In this sense we want to investigate the university students’ knowledge in the area of health at the Federal del Ceará University, Colombia regarding behaviors about contraception and STD prevention, since these future professionals will be an important source of information for the population. Data was obtained between May and June 2005 using a questionnaire of 12 objective questions about sexual education, sexual life and knowledge about pregnancy and STD prevention. Regarding information about sex, family, friends and school were the main sources of information. When asked if HIV could be transmitted through oral sex, 87.5% answered correctly, by responding that yes. There is certain knowledge about sexuality among the students. Nevertheless, there is still a lack of preventive knowledge regarding sexual health.La sexualidad humana es un componente importante en la formación del individuo. Sufrió importantes modificaciones a lo largo de la existencia de la vida humana, como la mayor divulgación de informaciones. Buscamos investigar el conocimiento de los universitarios del área de salud de la Universidad Federal del Ceará referente a las conductas de contracepción y prevención de DST, puesto que estas son una importante fuente de información para la población. La colecta de datos tuvo lugar entre mayo y junio de 2005 por medio de un cuestionario objetivo compuesto de 12 preguntas, acerca de la educación sexual, sexualidad y conocimiento en la prevención del embarazo no deseado y de DST. En cuanto a la orientación sexual, la familia, los amigos y la escuela fueron las principales fuentes de información. Preguntados si la transmisión del VIH se produce a través de sexo oral, 87,5% respondió correctamente al afirmar la cuestión como verdadera. Percibimos cierto conocimiento sobre la sexualidad entre los estudiantes, no obstante todavía hay carencias sobre algunos aspectos preventivos de salud sexual.A sexualidade humana é um importante componente na formação do indivíduo. Esta sofreu importantes modificações ao longo da existência da vida humana, como uma maior divulgação de informações. Assim, buscamos investigar o conhecimento de universitários da área da saúde acerca das condutas de contracepção e prevenção de DST, já que estes são importante fonte de informação para a população. A coleta de dados ocorreu entre maio e junho de 2005 por meio de questionário objetivo com 12 questões, abordando dados relacionados à orientação sexual, sexualidade e conhecimento sobre prevenção de DST e gravidez indesejada. Quanto à orientação sexual a família, amigos e a escola foram as principais fontes de informação. Questionados se a transmissão do HIV ocorre através de sexo oral, 87,5% responderam corretamente ao afirmar a questão como verdadeira. Percebemos certo conhecimento sobre a sexualidade entre os universitários, porém ainda há carências sobre alguns aspectos preventivos da saúde sexua

Strong interface-induced spin-orbit coupling in graphene on WS2

Interfacial interactions allow the electronic properties of graphene to be modified, as recently demonstrated by the appearance of satellite Dirac cones in the band structure of graphene on hexagonal boron nitride (hBN) substrates. Ongoing research strives to explore interfacial interactions in a broader class of materials in order to engineer targeted electronic properties. Here we show that at an interface with a tungsten disulfide (WS2) substrate, the strength of the spin-orbit interaction (SOI) in graphene is very strongly enhanced. The induced SOI leads to a pronounced low-temperature weak anti-localization (WAL) effect, from which we determine the spin-relaxation time. We find that spin-relaxation time in graphene is two-to-three orders of magnitude smaller on WS2 than on SiO2 or hBN, and that it is comparable to the intervalley scattering time. To interpret our findings we have performed first-principle electronic structure calculations, which both confirm that carriers in graphene-on-WS2 experience a strong SOI and allow us to extract a spin-dependent low-energy effective Hamiltonian. Our analysis further shows that the use of WS2 substrates opens a possible new route to access topological states of matter in graphene-based systems.Comment: Originally submitted version in compliance with editorial guidelines. Final version with expanded discussion of the relation between theory and experiments to be published in Nature Communication